2-(Pro-1-ynyl)-5-(5,6-dihydroxypenta-1,3-diynyl) thiophene induces apoptosis through reactive oxygen species-mediated JNK activation in human colon cancer SW620 cells

Anti-cervical cancer effects of Compound Yangshe granule through the PI3K/AKT pathway based on network pharmacology

ETHNOPHARMACOLOGICAL RELEVANCE

Compound Yangshe granule is a characteristic Chinese preparation against cervical cancer used at Fudan University Shanghai Cancer Center, and it consists of Hedyotis Diffusae Herba, Solani Lyrati Herba, Rubiae Radix et Rhizoma, Echinopsis Radix, Angelicae Sinensis Radix, Codonopsis Radix and Atractylodis Macrocephalae Rhizoma.

AIM OF THE STUDY

The objective of the current study was to investigate the preclinical efficacy of compound Yangshe granule against cervical cancer and elucidate the underlying mechanisms.

MATERIALS AND METHODS

Antitumor effect of the preparation was investigated in U14 cells in vitro and subcutaneous xenograft mice in vivo. The underlying mechanisms were investigated by through network pharmacological analysis and identified by in vitro study. The components of compound Yangshe granule were collected from the Traditional Chinese Medicine Systems Pharmacology database, and the corresponding targets were predicted by the SwissTargetPrediction database. The targets involved in cervical cancer were collected from the GeneCards, Online Mendelian Inheritance in Man and DrugBank databases. A protein‒protein interaction network was constructed by using the String platform. The drug-disease-target network was plotted by Cytoscape software. Kyoto Encyclopedia of Genes and Genomes and Gene Ontology enrichment analyses were performed to investigate hub targets.

RESULTS

After treatment with 0.5-10 mg/mL compound Yangshe granule, the survival rates of U14 cells gradually declined to 53.32% for 24 h, 23.62% for 48 h, and 12.81% for 72 h. The apoptosis rates of U14 cells gradually increased to 15.52% for 24 h, 23.87% for 48 h, and 65.01% for 72 h after treatment with 2-10 mg/mL compound Yangshe granule. After oral administration of compound Yangshe granule by xenograft mice, the tumor inhibition rates reached 52.27%, 74.62%, and 82.70% in the low, middle, and high dose groups, respectively. According to the network pharmacological analysis, quercetin, luteolin and naringenin were the most bioactive ingredients of the preparation. Kyoto Encyclopedia of Genes and Genomes pathway analysis showed that compound Yangshe granule may combat cervical cancer through the PI3K/AKT pathway.

CONCLUSION

In summary, network pharmacology combined with biological experiments demonstrated that the main bioactive components including quercetin, luteolin and naringenin could inhibit the tumor growth by regulating the PI3K/AKT pathway and Bcl-2 family. Thus, compound Yangshe granule may be a promising adjuvant therapy for cervical cancer.

An Overview of Potential Natural Photosensitizers in Cancer Photodynamic Therapy

Cancer is one of the main causes of death worldwide. There are several different types of cancer recognized thus far, which can be treated by different approaches including surgery, radiotherapy, chemotherapy or a combination thereof. However, these approaches have certain drawbacks and limitations. Photodynamic therapy (PDT) is regarded as an alternative noninvasive approach for cancer treatment based on the generation of toxic oxygen (known as reactive oxygen species (ROS)) at the treatment site. PDT requires photoactivation by a photosensitizer (PS) at a specific wavelength (λ) of light in the vicinity of molecular oxygen (singlet oxygen). The cell death mechanisms adopted in PDT upon PS photoactivation are necrosis, apoptosis and stimulation of the immune system. Over the past few decades, the use of natural compounds as a photoactive agent for the selective eradication of neoplastic lesions has attracted researchers' attention. Many reviews have focused on the PS cell death mode of action and photonanomedicine approaches for PDT, while limited attention has been paid to the photoactivation of phytocompounds. Photoactivation is ever-present in nature and also found in natural plant compounds. The availability of various laser light setups can play a vital role in the discovery of photoactive phytocompounds that can be used as a natural PS. Exploring phytocompounds for their photoactive properties could reveal novel natural compounds that can be used as a PS in future pharmaceutical research. In this review, we highlight the current research regarding several photoactive phytocompound classes (furanocoumarins, alkaloids, poly-acetylenes and thiophenes, curcumins, flavonoids, anthraquinones, and natural extracts) and their photoactive potential to encourage researchers to focus on studies of natural agents and their use as a potent PS to enhance the efficiency of PDT.

Thiophenes-Naturally Occurring Plant Metabolites: Biological Activities and In Silico Evaluation of Their Potential as Cathepsin D Inhibitors

Naturally, thiophenes represent a small family of natural metabolites featured by one to five thiophene rings. Numerous plant species belonging to the family Asteraceae commonly produce thiophenes. These metabolites possessed remarkable bioactivities, including antimicrobial, antiviral, anti-inflammatory, larvicidal, antioxidant, insecticidal, cytotoxic, and nematicidal properties. The current review provides an update over the past seven years for the reported natural thiophene derivatives, including their sources, biosynthesis, spectral data, and bioactivities since the last review published in 2015. Additionally, with the help of the SuperPred webserver, an AI (artificial intelligence) tool, the potential drug target for the compounds was predicted. In silico studies were conducted for Cathepsin D with thiophene derivatives, including ADMET (drug absorption/distribution/metabolism/excretion/and toxicity) properties prediction, molecular docking for the binding interaction, and molecular dynamics to evaluate the ligand-target interaction stability under simulated physiological conditions.

The Genus Echinops: Phytochemistry and Biological Activities: A Review

The genus Echinops belongs to the family of Asteraceae and comprises about 130 species. Many species belonging to the genus Echinops are traditionally used as medicinals mainly in Africa and Asia. The genus is reported to contain diverse secondary metabolites. The aim of this review is to critically evaluate the available research reports on the genus and systematically organize the findings. Information for this study was obtained using various search engines including PubMed and Google Scholar. This review revealed that the genus is used traditionally to treat pain, inflammation, respiratory diseases, diseases caused by different microorganisms, as an aphrodisiac, to fasten expulsion of placenta, and for removal of renal stones. More than 151 secondary metabolites have been reported from the genus in which thiophenic compounds held the biggest share. Various extracts, essential oils, and isolated compounds from members of this genus are shown to exhibit different biological effects mainly anti-microbial, anti-proliferative, and anti-inflammatory. However, there are a number of species in this genus that are claimed to have traditional medicinal uses but their biological effect not yet been evaluated.

Chrysophanol Suppresses Hypoxia-Induced Epithelial-Mesenchymal Transition in Colorectal Cancer Cells

Colorectal cancer (CRC) is a common human malignancy, accounting for 600,000 death cases annually worldwide. Chrysophanol is a naturally occurring anthraquinone compound and exhibits anti-neoplastic activities. This study aims to explore the biological effects of chrysophanol on CRC metastasis and the relevant underlying mechanism. Cell proliferation assay, wound scratch assay, and Transwell invasion assay were used to examine the effect of chrysophanol on proliferation, migration, and invasion of CRC cells. Hypoxia-inducible factor-1α (HIF-1α) shRNA was utilized to transfect CRC cells to examine the role of HIF-1α in chrysophanol suppression of hypoxia-induced epithelial to mesenchymal transition (EMT). The suppression effect of chrysophanol on hypoxia-induced EMT in vivo was also validated in xenograft tumor models. In the present study, our findings indicated that chrysophanol has the capability to suppress hypoxia-induced EMT in CRC in vitro and in vivo, and the possible mechanism involved is the inhibition of HIF-1α via modulating PI3k/Akt signaling pathway. Collectively, the results indicated that chrysophanol can be used as an EMT and cancer metastasis inhibitor in the treatment of CRC. Anat Rec, 302:1561-1570, 2019. © 2019 American Association for Anatomy.

DUB3 deubiquitinates and stabilizes NRF2 in chemotherapy resistance of colorectal cancer

The transcription factor nuclear factor (erythroid-derived 2)-like 2 (NRF2) is one of the master regulators that control hundreds of genes containing antioxidant response elements (AREs). The NRF2-ARE pathway plays a complex role in colorectal cancer (CRC). NRF2 activity is known to be regulated by KEAP1-CUL3 E3 ligase-mediated ubiquitination, indicating the importance of deubiquitination regulation. However, the deubiquitinase (DUB) of NRF2 remains unknown. Here, by screening a DUB library, we identified DUB3 as a DUB that remarkably stabilized NRF2. Further experiments demonstrated that DUB3 promoted NRF2 stability and transcriptional activity by decreasing the K48-linked ubiquitination of NRF2. Coimmunoprecipitation studies revealed interactions between NRF2 and DUB3, as well as between KEAP1 and DUB3, indicating that NRF2, DUB3, and KEAP1 formed a large functional complex. Importantly, ectopic expression of DUB3 caused NRF2-dependent chemotherapy resistance in colon cancer cell lines. Thus, to the best of our knowledge, our findings are the first to identify DUB3 as a NRF2 DUB and may provide a new strategy against chemotherapy resistance in CRC and other NRF2-related diseases.

The dietary flavone luteolin epigenetically activates the Nrf2 pathway and blocks cell transformation in human colorectal cancer HCT116 cells

Colorectal cancer remains a leading malignancy in humans. The importance of epigenetic modification in the development of this disease is now being recognized. The reversible and dynamic nature of epigenetic modifications provides a promising strategy in colorectal cancer chemoprevention and treatment. Luteolin (LUT), a flavone dietary phytochemical, can modulate various signaling pathways involved in carcinogenesis. Many studies have demonstrated that LUT inhibits colorectal carcinogenesis by activating the Nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant-responsive element (ARE) pathway. However, the potential epigenetic mechanism underlying Nrf2/ARE pathway activation remains unclear. In this study, we aimed to explore the anticancer potential of LUT in human colon cancer cells and the epigenetic regulation of the Nrf2/ARE pathway. Specifically, our data showed that LUT suppressed cell proliferation and cellular transformation of HCT116 and HT29 cells in a dose-dependent manner. Additionally, quantitative real-time polymerase chain reaction and Western blot analysis were performed to determine the mRNA and protein expression of Nrf2 and its downstream genes after LUT treatment. Bisulfite genomic sequencing revealed that methylation of the Nrf2 promoter region was decreased by LUT, corresponding with the increased mRNA expression of Nrf2. Decreased protein levels and enzyme activities of epigenetic modifying enzymes, such as DNA methyltransferases (DNMTs) and histone deacetylases (HDACs), were also observed in LUT-treated HCT116 cells. In summary, our findings suggest that LUT may exert its antitumor activity in part via epigenetic modifications of the Nrf2 gene with subsequent induction of its downstream antioxidative stress pathway.

Anticancer properties of thiophene derivatives in breast cancer MCF-7 cells

Substitutions in thiophene structure give rise to new derivatives with different biological and pharmacological activities. The present study investigated the cytotoxicity activity of some thiophene derivatives in breast cancer cells maintained in two-dimensional (2D) or in three-dimensional (3D) culture and evaluated the anticancer mechanism of these compounds. Cytotoxicity assays were performed against untransformed cells and against breast cancer cell MCF-7. Apoptosis analysis and in-vitro migration assay were also performed to evaluate the mechanism of induction of cell death. All thiophene derivatives reduced the cell viability in breast cancer cells, showing cytotoxic activity (IC50<30 µmol/l), and SB-200 compound showed the best selectivity index in MCF-7 cells compared with doxorubicin in 2D culture. All thiophene derivatives significantly induced G0/G1 phase cell cycle arrest. However, only SB-83 treatment was effective against motility of MCF-7 cells in 2D culture (P=0.0059). The SB-200 derivative treatment induced an increased proportion of acridine orange/Hoechst double-stained cells (35.35 vs. 3.14%, P=0.0002) compared with nontreated cells, with apoptosis morphological alterations independent of caspase 7 activation (P>0.05). MCF-7 cells became less responsive to SB-200 and to doxorubicin in 3D culture compared with cells in 2D culture (higher IC50 values); however, SB-200 showed a better cytotoxic effect compared with doxorubicin in 3D culture. Therefore, the current study provides an insight into anticancer potential of thiophene derivatives, and further studies should be conducted to understand the mechanism by which thiophene derivatives act on cancer cells.

The NRF2 transcription factor plays a dual role in colorectal cancer: A systematic review

BACKGROUND

Colorectal cancer is one of the most common cancers worldwide, and is influenced by the interplay of various factors, including a very strong genetic component. For instance, incorrect mitochondrial biogenesis is correlated with increased risk of developing colorectal cancer. Thus, it is important to understand the consequences of changes in both the expression and the correct function of the transcription factors that regulate mitochondrial biogenesis, namely NRF2.

OBJECTIVES

The main objective of this paper is to characterise the relationship between NRF2 and colorectal cancer by compiling data from an exhaustive literature search.

METHODS

Information was obtained by defining specific search terms and searching in several databases. After a strict selection procedure, data were tabulated and the relationships between articles were assessed by measuring heterogeneity and by constructing conceptual maps.

RESULTS AND DISCUSSION

We found a general consensus in the literature that the presence of oxidizing agents as well as the inhibition of the NRF2 repressor Keap1 maintain NRF2 expression at basal levels. This predominantly exerts a cytoprotective effect on cells and decreases risk of colorectal cancer. However, if NRF2 is inhibited, protection against external agents disappears and risk of colorectal cancer increases. Interestingly, colorectal cancer risk is also increased when NRF2 becomes overexpressed. In this case, the increased risk arises from NRF2-induced inflammation and resistance to chemotherapy.

CONCLUSION

The proper basal function of NRF2 and Keap1 are essential for preventing oncogenic processes in the colon. Consequently, any disruption to the expression of these genes can promote the genesis and progression of colon cancer.

Development of Certain Protein Kinase Inhibitors with the Components from Traditional Chinese Medicine

Traditional Chinese medicines (TCMs) have been used in China for more than two thousand years, and some of them have been confirmed to be effective in cancer treatment. Protein kinases play critical roles in control of cell growth, proliferation, migration, survival, and angiogenesis and mediate their biological effects through their catalytic activity. In recent years, numerous protein kinase inhibitors have been developed and are being used clinically. Anticancer TCMs represent a large class of bioactive substances, and some of them display anticancer activity via inhibiting protein kinases to affect the phosphoinositide 3-kinase, serine/threonine-specific protein kinases, pechanistic target of rapamycin (PI3K/AKT/mTOR), P38, mitogen-activated protein kinase (MAPK) and extracellular signal-regulated kinases (ERK) pathways. In the present article, we comprehensively reviewed several components isolated from anticancer TCMs that exhibited significantly inhibitory activity toward a range of protein kinases. These components, which belong to diverse structural classes, are reviewed herein, based upon the kinases that they inhibit. The prospects and problems in development of the anticancer TCMs are also discussed.